Crank Position Sensor - '96 LT4
Thread Starter
Burning Brakes
Joined: Mar 1999
Posts: 1,150
Likes: 138
From: Raymore Missouri
Crank Position Sensor - '96 LT4
After spending considerable time looking for the source of my oil leak, I'm almost convinced it is the Crank Position Sensor O-ring. The cross member is covered in oil, but really, that's it.
Has anyone replaced this o-ring? How do you get to the crank position sensor? To paraphrase the service manual, it says, "Raise car, remove sensor." Very helpful, indeed :rolleyes: So, under the car, I think I can just barely see the bolt that holds this thing in, but there's no way I'm going to get anything on it to remove it.
From above, I am down to the Optispark, since the water pump is still out. Without removing the Optispark, I cannot see the bolt for the CPS. I guess I could remove the Optispark, but I am just so curious how in the heck you're supposed to remove the thing from underneath the car :confused: :confused:
Thanks for any suggestions...
Mike
Has anyone replaced this o-ring? How do you get to the crank position sensor? To paraphrase the service manual, it says, "Raise car, remove sensor." Very helpful, indeed :rolleyes: So, under the car, I think I can just barely see the bolt that holds this thing in, but there's no way I'm going to get anything on it to remove it.
From above, I am down to the Optispark, since the water pump is still out. Without removing the Optispark, I cannot see the bolt for the CPS. I guess I could remove the Optispark, but I am just so curious how in the heck you're supposed to remove the thing from underneath the car :confused: :confused:
Thanks for any suggestions...
Mike
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Joined: Apr 2000
Posts: 15,344
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From: Texas
Re: Crank Position Sensor - '96 LT4 (zyal8r)
Believe it or not, it is possible. Takes an 8mm wrench, contorted hands, an 1/8 of a turn at a time on the bolt, and LOTS of patience.
I had this same leak. Car was under warranty at the time. They replaced the CPS o-ring. Still leaked. I replaced the o-ring. Still Leaked. The dealer replaced all three seals in the front cover (Opti, crank, waterpump driveshaft) and it still leaked. One little drop would hang off the CPS and the crossmember had oil on it. Turned out the crankshaft hub had a grove worn in it from the seal. The dealer replaced the hub...no more leak. That was 34k miles ago :)
I had this same leak. Car was under warranty at the time. They replaced the CPS o-ring. Still leaked. I replaced the o-ring. Still Leaked. The dealer replaced all three seals in the front cover (Opti, crank, waterpump driveshaft) and it still leaked. One little drop would hang off the CPS and the crossmember had oil on it. Turned out the crankshaft hub had a grove worn in it from the seal. The dealer replaced the hub...no more leak. That was 34k miles ago :)
Thread Starter
Burning Brakes
Joined: Mar 1999
Posts: 1,150
Likes: 138
From: Raymore Missouri
Re: Crank Position Sensor - '96 LT4 (96GS#007)
Turned out the crankshaft hub had a grove worn in it from the seal. The dealer replaced the hub...no more leak.
Thanks again,
Mike
Race Director
Joined: Apr 2000
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From: Texas
Re: Crank Position Sensor - '96 LT4 (zyal8r)
Just want to clarify... are you saying that the crankshaft hub had a groove worn in it from the o-ring (parts list I have also refers to it as a seal)?
:cheers:
Race Director
Joined: Mar 1999
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From: Stafford, Virginia Kittah, Kittah, Kittah...
Re: Crank Position Sensor - '96 LT4 (96GS#007)
Just want to clarify... are you saying that the crankshaft hub had a groove worn in it from the o-ring (parts list I have also refers to it as a seal)?
Not the o-ring. The hub had a groove worn in it from the crankshaft seal. This is the seal that's pressed into the front (timing chain) cover. Gotta pull the balancer/hub assembly to change the seal.
:cheers:
Not the o-ring. The hub had a groove worn in it from the crankshaft seal. This is the seal that's pressed into the front (timing chain) cover. Gotta pull the balancer/hub assembly to change the seal.
:cheers:
I had this same problem... There is a sleve kit for the hub, but you do need to replace the seal... My 96 had this leak at around 40K miles... Also the Opti drive and water pump drive seals had started leaking although not bad... I replaced them myself since I was chaning out an optispark anyway...
[Modified by wake, 8:47 PM 12/30/2002]
Racer
Joined: Jan 2002
Posts: 341
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From: Cave Creek AZ
Re: Crank Position Sensor - '96 LT4 (zyal8r)
I just replaced mine. You need to get the car up high enough so that you can maneuver under there. My was about 10 inches off the ground. I used a 1/4" drive ratchet and the best fitting socket I had. The bolt is not very tight. (spec is 35-53 lb-in). You can get the ratchet and socket up in there pretty easily once the connector is off. Pull off the connector, remove the bolt, pull out the sensor. Remove the old O ring and clean everything up including the hole in the timing chain cover. Roll the new O ring onto the sensor and reinstall. Remember that the bolt torque is pretty light, so don't snap it off. :)
